Bio-soluble fiber-based mixtures and their use in matrices for infrared emission

Abstract

Bio-soluble fiber-based matrices for use in infrared heaters prepared from mixtures comprising (a) bio-soluble fibers, (b) a particulate material capable of infrared emissivity, and (c) a binder comprising colloidal silica, wherein said bio-soluble fibers are present in an amount of about 60% by weight said particulate material capable of infrared emissivity is present in an amount of about 19% by weight said colloidal silica is present in an amount of about 17% by weight, said starch is present in an amount of about 3% by weight, and further comprises about 1% by weight of a water repellant agent based on the total weight of the mixture.

1 . An mixture comprising:
 (a) bio-soluble fibers;   (b) a particulate material capable of infrared emissivity; and   (c) a binder comprising colloidal silica.   
   
   
       2 . The mixture of  claim 1 , wherein said mixture is aqueous. 
   
   
       3 . The mixture of  claim 2 , wherein at least about ⅔ by weight of said binder is said colloidal silica, based on the total weight of said binder. 
   
   
       4 . The mixture of  claim 3 , wherein said colloidal silica has an average particle size of about 70 nm and a surface area of about 70 m 2 /g. 
   
   
       5 . The mixture of  claim 4 , wherein said colloidal silica is in the form of an aqueous dispersion having a specific gravity of about 1.39, a pH at 25° C. of about 9.0 to about 9.5, and a viscosity at 25° C. of about 15 cp. 
   
   
       6 . The mixture of  claim 1 , wherein said bio-soluble fibers comprise silica magnesia, silicon dioxide, calcium oxide, magnesium oxide, man-made vitreous fibers, or mixtures thereof. 
   
   
       7 . The aqueous mixture of  claim 1 , wherein said particulate material capable of infrared emissivity comprises silicon carbide, silicon, silicon nitride, silicon carbonitride, and mixtures thereof. 
   
   
       8 . The mixture of  claim 1 , wherein said bio-soluble fibers are present in an amount of from about 54% to about 66% by weight, said particulate material capable of infrared emissivity is present in an amount of from about 16% to about 23% by weight, and said binder is present in an amount of from about 16% to about 23% by weight, based on the total solids weight of the aqueous mixture. 
   
   
       9 . The mixture of  claim 1 , further comprising a water repellant or water-proofing agent, an opacifier, or mixtures thereof. 
   
   
       10 . The mixture of  claim 5 , wherein said binder comprises an organic binder. 
   
   
       11 . The mixture of  claim 10 , wherein said organic binder is starch. 
   
   
       12 . The mixture of  claim 11 , wherein said bio-soluble fibers are present in an amount of about 60% by weight, said particulate material capable of infrared emissivity is present in an amount of about 19% by weight, said colloidal silica is present in an amount of about 17% by weight, said starch is present in an amount of about 3% by weight, and further comprises about 1% by weight of a water repellant agent, based on the total solids weight of the aqueous mixture. 
   
   
       13 . A process for forming a bio-soluble fiber-based matrix comprising molding the mixture of  claim 1  to a desired shape. 
   
   
       14 . A bio-soluble fiber-based matrix prepared by the process of  claim 13 . 
   
   
       15 . The bio-soluble fiber-based matrix of  claim 14 , wherein said matrix comprises (1) bio-soluble fibers in an amount in the range of from about 60% to about 75% by weight, (2) particulate material capable of infrared emissivity in an amount in the range of from about 12.5% to about 20% by weight, and (3) binder comprising colloidal silica in an amount in the range of from about 12.5% to about 20% by weight, based on the total weight of the matrix. 
   
   
       16 . An infrared heating unit comprising the bio-soluble fiber-based matrix of  claim 15 . 
   
   
       17 . A process for forming a bio-soluble fiber-based matrix comprising molding the mixture of  claim 12  to a desired shape. 
   
   
       18 . A bio-soluble fiber-based matrix prepared by the process of  claim 17 . 
   
   
       19 . The bio-soluble fiber-based matrix of  claim 18 , wherein said matrix comprises (1) bio-soluble fibers in an amount in the range of from about 60% to about 75% by weight, (2) particulate material capable of infrared emissivity in an amount in the range of from about 12.5% to about 20% by weight, and (3) binder comprising colloidal silica in an amount in the range of from about 12.5% to about 20% by weight, based on the total weight of the matrix. 
   
   
       20 . An infrared heating unit comprising the bio-soluble fiber-based matrix of  claim 19 .